This article mainly related with storage backup and recovery. It describes what are all the hardware’s used in the storage backup and recovery technologies. So many hardware components used in the Storage Backup areas. It is not the article to bring out the functions of that hardware parts. It gives the information and related technical details of that hardware used in the storage backup and recovery technology.
There are three main important hardware’s are used in the storage backup and recovery technology. They are Server, Subsystems and Switches. Each one has its own hardware parts. Let’s see the information and technical details of this hardware parts.
Server – Master Server
The Master server performs all Backup administrative functions and controls the backup scheduling for each media server. The requirements needed for Master Server,
o I/O Connectivity
o Operating System
o Backup Software
The media server performs the backup operations under the direction of the master, with all backup data stored locally on the media server and its respective storage devices. The same above Master Server requirements are applicable to Media Server also.
DAS, SAN, NAS Storage Subsystems
Direct attached storage (DAS), storage area network (SAN), and network-attached storage (NAS) are the three basic types of storage subsystems used in Storage backup hardware management. DAS is the basic building block in a storage system, and it can be employed directly or indirectly when used inside SAN and NAS systems. NAS is the highest layer of storage and can be built on top of a SAN or DAS storage system. SAN is somewhere between a DAS and a NAS.
Hardware used in the Storage subsystem – SCSI
It is abbreviated like Small Computer System Interface. It is the famous storage subsystem component used in all medium and small level computer interfaces. A mechanism called ‘Cable Sharing’ used here. It can support the data transfer rate up to 320 MB/s.
Parallel Advanced technology Attachment is shortly named as PATA. It can support data transfer up to 133 MB/s. Nowadays SATA replaces this PATA in all areas. But the recent version UDMA133 is used in some subsystems depends upon the customer requirement.
Serial Advanced Technology Attachment is commonly known as SATA. It is the very common hard disk interface used in all personal systems. One SATA port permits one device to connect to it.
It means Serial Attached SCSI. The name itself tells, it can be seen as a merged SCSI and SATA interface. It has various data transfer rates like 185, 374, 750, and 1,500 MB/s. SATA devices can connect to SAS but SAS devices can’t connect with SATA ports. It is specifically designed for the high-end servers. SAS offers the best of SCSI and SATA.
Fibre Channel has a main advantage of its length. It works the same like SATA, but it can covers the distance up to 2kms (Example: Single Mode Fibre). FC offers speeds of 100, 200, and 400 MB/s.
Internet SCSI is shortly known as iSCSI. It is normally used in all LANs. It is Low-cost alternative to FC. Easier to manage because it uses the common TCP/IP protocol and common Ethernet switches.
ATA over Ethernet. It is a very low cost alternative to iSCSI. It encapsulates ATA commands into low-level Ethernet frames and avoids using TCP/IP. A lot of add-on initiator/target software will support both iSCSI and AoE.
A switch is something that is used to turn on or off various electronic devices. However, in computer networking, a switch is used to connect multiple computers with each other. Since it is an external device it becomes part of the hardware peripherals used in the operation of storage backup and recovery. This connection has done within an existing Local Area network (LAN) only and is identical to an Ethernet hub in terms of appearance except with more intelligence. These switches not only receive data packets, but also have the ability to inspect them before passing them on to the next computer. That is, they can figure out the source, the contents of the data, and identify the destination as well. Because of this uniqueness; it sends the data to the relevant connected system only, thereby using less bandwidth at high performance rates. Ethernet switches were used to provide connections and link aggregation between the backup clients, media servers, and master server using network speeds of 100 Mb/sec, 1 Gb/sec, and 10 Gb/sec.
SAN switches were used to provide Fibre Channel connections between the Backup media servers and the tape libraries. The below listed companies are working with SAN switches worldwide.
Author: Muthu Senthil Kumar M